libavcodec/zerocodec.c
0e714f88
 /*
  * ZeroCodec Decoder
  *
  * Copyright (c) 2012, Derek Buitenhuis
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
 #include <zlib.h>
 
 #include "avcodec.h"
594d4d5d
 #include "internal.h"
1d9c2dc8
 #include "libavutil/common.h"
0e714f88
 
 typedef struct {
     AVFrame  previous_frame;
     z_stream zstream;
 } ZeroCodecContext;
 
 static int zerocodec_decode_frame(AVCodecContext *avctx, void *data,
df9b9567
                                   int *got_frame, AVPacket *avpkt)
0e714f88
 {
     ZeroCodecContext *zc = avctx->priv_data;
     AVFrame *pic         = avctx->coded_frame;
     AVFrame *prev_pic    = &zc->previous_frame;
     z_stream *zstream    = &zc->zstream;
29facc1e
     uint8_t *prev        = prev_pic->data[0];
     uint8_t *dst;
0e714f88
     int i, j, zret;
 
     pic->reference = 3;
 
6c8fdfc5
     if (avpkt->flags & AV_PKT_FLAG_KEY) {
         pic->key_frame = 1;
         pic->pict_type = AV_PICTURE_TYPE_I;
     } else {
         if (!prev) {
29facc1e
             av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
6c8fdfc5
             return AVERROR_INVALIDDATA;
         }
2ddf7c88
 
         prev += (avctx->height - 1) * prev_pic->linesize[0];
 
6c8fdfc5
         pic->key_frame = 0;
         pic->pict_type = AV_PICTURE_TYPE_P;
     }
 
0e714f88
     zret = inflateReset(zstream);
     if (zret != Z_OK) {
29facc1e
         av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret);
         return AVERROR_INVALIDDATA;
0e714f88
     }
 
594d4d5d
     if (ff_get_buffer(avctx, pic) < 0) {
616fd4fe
         av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
         return AVERROR(ENOMEM);
     }
 
0e714f88
     zstream->next_in  = avpkt->data;
     zstream->avail_in = avpkt->size;
 
2ddf7c88
     dst = pic->data[0] + (avctx->height - 1) * pic->linesize[0];
0e714f88
 
     /**
      * ZeroCodec has very simple interframe compression. If a value
      * is the same as the previous frame, set it to 0.
      */
 
afa61290
     for (i = 0; i < avctx->height; i++) {
         zstream->next_out  = dst;
         zstream->avail_out = avctx->width << 1;
0e714f88
 
afa61290
         zret = inflate(zstream, Z_SYNC_FLUSH);
         if (zret != Z_OK && zret != Z_STREAM_END) {
616fd4fe
             avctx->release_buffer(avctx, pic);
afa61290
             av_log(avctx, AV_LOG_ERROR,
29facc1e
                    "Inflate failed with return code: %d.\n", zret);
             return AVERROR_INVALIDDATA;
afa61290
         }
0e714f88
 
afa61290
         if (!(avpkt->flags & AV_PKT_FLAG_KEY))
0e714f88
             for (j = 0; j < avctx->width << 1; j++)
                 dst[j] += prev[j] & -!dst[j];
 
2ddf7c88
         prev -= prev_pic->linesize[0];
         dst  -= pic->linesize[0];
0e714f88
     }
 
     /* Release the previous buffer if need be */
     if (prev_pic->data[0])
         avctx->release_buffer(avctx, prev_pic);
 
df9b9567
     *got_frame = 1;
0e714f88
     *(AVFrame *)data = *pic;
 
6c8fdfc5
     /* Store the previous frame for use later.
      * FFSWAP ensures that e.g. pic->data is NULLed. */
     FFSWAP(AVFrame, *pic, *prev_pic);
 
0e714f88
     return avpkt->size;
 }
 
 static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
 {
     ZeroCodecContext *zc = avctx->priv_data;
     AVFrame *prev_pic    = &zc->previous_frame;
 
     inflateEnd(&zc->zstream);
 
     /* Release last frame */
     if (prev_pic->data[0])
         avctx->release_buffer(avctx, prev_pic);
 
     av_freep(&avctx->coded_frame);
 
     return 0;
 }
 
 static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
 {
     ZeroCodecContext *zc = avctx->priv_data;
     z_stream *zstream    = &zc->zstream;
     int zret;
 
716d413c
     avctx->pix_fmt             = AV_PIX_FMT_UYVY422;
0e714f88
     avctx->bits_per_raw_sample = 8;
 
     zstream->zalloc = Z_NULL;
     zstream->zfree  = Z_NULL;
     zstream->opaque = Z_NULL;
 
     zret = inflateInit(zstream);
     if (zret != Z_OK) {
29facc1e
         av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret);
0e714f88
         return AVERROR(ENOMEM);
     }
 
     avctx->coded_frame = avcodec_alloc_frame();
     if (!avctx->coded_frame) {
         av_log(avctx, AV_LOG_ERROR, "Could not allocate frame buffer.\n");
         zerocodec_decode_close(avctx);
         return AVERROR(ENOMEM);
     }
 
     return 0;
 }
 
 AVCodec ff_zerocodec_decoder = {
     .type           = AVMEDIA_TYPE_VIDEO,
     .name           = "zerocodec",
36ef5369
     .id             = AV_CODEC_ID_ZEROCODEC,
0e714f88
     .priv_data_size = sizeof(ZeroCodecContext),
     .init           = zerocodec_decode_init,
     .decode         = zerocodec_decode_frame,
     .close          = zerocodec_decode_close,
     .capabilities   = CODEC_CAP_DR1,
     .long_name      = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),
 };